Twitter is ending its practice of dark ads, which are promoted posts that can only be seen by the people advertisers pay to target.

In the coming weeks, Twitter will display all ads, including these promoted-only posts, in a new "Transparency Center," the company announced Tuesday.

Twitter's move comes as the company is under intense scrutiny from Congress following the revelation that Kremlin-linked trolls used its platform in an attempt to sow discord in American politics during and after the 2016 presidential election. After meeting with the Senate Intelligence Committee about the issue last month, Twitter was lambasted by Sen. Mark Warner, who called the company's presentation to the committee "deeply disappointing" and inadequate in almost every way.

Last week, Sens. Warner and Amy Klobuchar introduced a bill that would require social media companies to be more transparent about political advertising on their platforms. Now, Twitter is being proactive. Many tech companies prefer to introduce reforms on their own, rather than wait for Congress to mandate them to change.

"We look forward to engaging with Members of Congress and other key stakeholders on these issues as the legislative process continues," the company said in its blog post.

Immediately after Twitter announced its plans, Sen. Warner expressed approval in a tweet, calling it "a good first step."

Twitter’s Transparency Center will detail all ads running on the platform, how long those ads have been live, the ads themselves, and more. For political ads, the Transparency Center will show all ads (past and present), how much has been spent on each ad campaign, who is paying for the ads, basic targeting details, among other information. Twitter will also introduce a new “visual political ad indicator” that shows up when a political ad is running. It said it will "include stricter requirements on who can serve these ads and limit targeting options."

Alex Kantrowitz is a senior technology reporter for BuzzFeed News and is based in San Francisco. He reports on social and communications.